This disclosure relates in general to assigning a content objects to multiple nodes in a hierarchy and to performing characterizations of or searches for content using the assignments and hierarchy.
Characterization of content objects can assist in predicting content objects of interest to a user. For example, the characterization can be used to suggest content objects within a category of interest to a user or to identify content objects responsive to a user's search. However, the utility of the characterization depends on how the characterization is performed in the first place. The characterization can be difficult because different users can use different terms to search for a same content object.